In exiting pulsator type washing machines, drain holes are formed in an inner tub, the inner tub which is a washing tub communicates with an outer tub which is a water container. Water filling the space between the side walls of the inner tub and the outer tub does not participate in washing, and only water in the inner tub really participates in washing, so that water resources are greatly wasted. In addition, the concentration of detergents/washing powder in washing solutions is reduced by excessive water between the inner and outer tubs. Meanwhile, as the water frequently flows in and out of the inner and outer tubs, after continuous usage, the area between the side walls of the inner tub and the outer tub becomes a space containing dirt and dust. And incrustation in running water, free substances of the washing powder, cellulose of clothes, organic matters of human bodies and dust and germs brought by the clothes are extremely prone to be retained between the side walls of the inner tub and the outer tub. A large quantity of dirt accumulated in the washing machine after long time use causes breeding of mould, and if the dirt is not removed, at the next time of washing, the germs will be attached to the clothes and brought to the human bodies to cause cross infection.
Patent 201210011789.1 relates to a sealed inner tub comprising a side wall and a bottom integrally connected, wherein the side wall and the bottom are hermetically arranged, a water drain groove is arranged on the top of the side wall, and water in the inner tub and clothes completely drains to the outside of the inner tub through the water drain groove. The patent also relates to a washing machine with the sealed inner tub and a washing method of the washing machine. Due to the no-hole design of the inner tub, washing water does not need to enter the area between the inner tub and the outer tub, so that the purpose of greatly saving the washing water is achieved. Meanwhile, dirt and bred germs retained in the area between the inner tub and the outer tub do not contact the clothes in the inner tub through water flows, so that cross infection of the germs can be effectively avoided, and thus the washing machine is more sanitary and environment-friendly and safer to use. However, all water drains from the upper part, and lint and silt in the water cannot be completely discharged and remained in the inner tub, so that pollution is caused again at the next time of washing clothes.
Patent 200420107890.8 relates to a full-automatic washing machine mainly comprising a casing, a washing and dewatering tub, a water container tub and a drive device, wherein the water container tub is installed outside the washing and dewatering tub and fixedly connected with the casing. A sealing device is arranged between the bottom surface of the inner wall of the water container tub and the bottom surface of the outer wall of the washing and dewatering tub, and a sealed cavity is formed in the sealing device. No through hole is formed in the outer side wall of the washing and dewatering tub, and a drain hole communicating with the sealed cavity is formed in the bottom of the washing and dewatering tub; and a first drain hole communicating with a drain pipe is formed in the water container tub, and a drain valve is arranged on the drain pipe. The water container tub is fixedly connected with the casing via a suspension rod. One end of the suspension rod is connected with the inner wall of the upper end of the casing, while the other end is connected with the outer wall of the water container tub. But after long-time operation, the sealing structure is prone to leak water due to wearing, and if the water is poor in quality and high in sediment concentration, the service life of the sealing structure may be greatly reduced and the sealing structure cannot provide a proper function. The full-automatic washing machine is not used under the condition of large washing capacity either, and poor in reliability.
A preferred scheme is as follows: the drain hole in the bottom of the inner tub is not located in the center of the bottom of the inner tub, but formed in an off-centered side of the bottom of the inner tub; a control structure of the drain hole is arranged at the bottom of the outer tub. If the control structure is arranged on the off-centered side of the bottom of the inner tub, the inner tub rotates during dewatering, and thus the inner tub needs to be positioned every time after dewatering or before washing water feeding to ensure that the drain hole of the inner tub is aligned with the control structure of the drain hole of the outer tub, and also ensure that the inner tub does not rotate during washing.
Therefore, the present disclosure is provided.